Concrete slab form panel-supporting bracket



Aug. 20, 1968 w. D. WILLIAMS 3,397,358

CONCRETE SLAB FORM PANEL-SUPPORTING BRACKET F'iled April 4, 1966 2Sheets-Sheet 1 /NVENTOR WALTER 0. w/ AMS W CONCRETE SLAB FORMPANEL-SUPPORTING BRACKET Filed April 4, 1966 Aug. 20, 1968 w. D.WILLIAMS 2 Sheets-Sheet 2 //v VEN TOR LTER 0. L/AMS WA BY United StatesPatent 3,397,858 CONCRETE SLAB FORM PANEL-SUPPORTING BRACKET Walter D.Williams, River Forest, 111., assignor to Symons Mfg. Company, DesPlaines, 111., a corporation of Delaware Filed Apr. 4, 1966, Ser. No.539,782 6 Claims. (Cl. 249-18) ABSTRACT OF THE DISCLOSURE Apanel-supporting bracket assembly which, in combination with anidentical bracket assembly, serves to support two wooden beams inparallelism and in bridging relationship with respect to an odddimension opening between two horizontal Steel-Ply panels so that aplywood sheet may be supported on the beams to fill the opening.

The panel-supporting bracket comprising the present invention isdesigned for use primarily in connection with a panel-supportingstringer assembly of the type which forms the subject matter of UnitedStates Patent No. 3,052,008, granted on Sept. 4, 1962, and entitledPanel- Supporting Stringer Assembly for a Concrete Floor Slab. Thestringer assembly, in turn, is designed for use specifically inconnection with a particularly system for erecting concrete buildingstructures, the system being illustrated and described in United StatesPatent No. 3,130,- 470, granted on Apr. 28, 1964, and entitled ConcreteWall Form Installation. Still further, the system itself involves theuse of special concrete slab form panels which are commonly known asSteel-Ply panels and are in the form of prefabricated units like thoseshown and described in United States Patent No. 2,997,769, granted onAug. 29, 1961, and entitled Tie Rod Assembly for Concrete Wall FormPanels. The building erection system, as well as the panel-supportingstringer assemblies and the slab form panels which are employed inconnection with the system, have common proprietary ownership in SymonsMfg. Company of Des Plaines, 111., and the present panel-supportingbracket is useful only in connection with a building erecting systememploying stringer assemblies of the type forming the subject matter ofsaid Patent No. 3,052,008. The principal purpose of the presentpanel-supporting bracket is to enable the system to be used inconnection with slab form panels other than Steel-Ply panels,specifically flat plywood panels which are of rectangula configurationand unlike Steel-Ply panels employ no metallic studding or reinforcingframes.

The development of the present panel-supporting bracket is attributablelargely to a matter of economics. Many building contractors have accessto, and often oWnership in, sources of plywood. When it is consideredthat, roughly speaking, the current cost of a Steel-Ply panel is on theorder of two dollars and fifty cents per square foot so that a panelmeasuring four feet by eight feet costs approximately seventy-fivedollars and it is also considered that plywood of a thickness requisiteto support a concrete slab costs only on the order of seven cents persquare foot, it is not surprising that many contractors who have accessto an inexpensive source of plywood take advantage of its availabilityand substitute plain plywood panels for Steel-Ply panels when they areable conveniently so to do. In the building erecting system ofaforementioned Patent No. 3,130,470, reliance is placed upon themetallic reinforcing frames of the Steel-Ply panels to support the endsof the panels from the special stringer assemblies which are involvedin, and form parts of, the system as a whole. Ordinarily, for slabconstruction work, Steel-Ply panels which have standard dimensions offour feet by eight feet are employed. Plain rectangular plywood panelswhich are of equivalent size and have no metallic reinforcing frames arenot sulficiently strong to withstand the load of the concrete which mustbe poured upon them to produce a slab. Furthermore, the small thicknessof a plain plywood panel is only a fraction of the overall thickness ofa Steel-Ply panel, and thus there are no facilities for adequatelysupporting a plain plywood panel in position between the adjacentstringer assemblies which, according to the Symons building erectingsystem, are of special construction. Lack of the ability of a contractorto utilize the plywood which conveniently is available to him in theSymons system of building erection involving floor slabs has precludedsuch contractor from utilizing the system as a whole and, therefore, hehas been obliged to content himself with the use of other buildingerecting systems which will enable him to use his source of plywood butare nevertheless less effective, practical and efficient.

The panel-supporting bracket of the present invention is designed toovercome the abovenoted limitation which is imposed upon a contractorwho is thus precluded from utilizing plain plywood panels in connectionwith the Symons system of building erection and, toward this end, theinvention contemplates the provision of a r latively simple andinexpensive panel-supporting bracket which will adequately support arectangular sheet of plywood that is dimensioned commensurately with astandard Steel-Ply panel; which will correctly position the plywoodpanel so that its upper face lies flush with the upper face of anadjustable stringer like that of aforementioned Patent No. 3,052,008 inorder to produce an unbroken pouring surface for the concrete; whichwill reinforce the plain plywood panel so that it will adequatelysupport the load; which will enable stripping of the plain panel fromthe building erecting system as soon as the poured slab has becomeself-supporting; and which otherwise, by its use, function with theassociated plain panel in the manner of a Steel-Ply panel in that itrequires no deviation from the method steps which are involved inpracticing the Symons system of concrete building erection.

For a full understanding of the nature of the present panel-supportingbracket, as well as the use to which it is put, it is necessary that thecharacter and mode of operation of the adjustable panelsupportingstringers with which the bracket is associated be thoroughly understood.The adjustable stringer assemblies of a Symons building erecting systemare so designed as to support a horizontal series of Steel-Ply panels sothat the upper faces of the plywood facings of the panels are coplanar.The stringers proper of the assemblies when in their operative panelsupporting position present upper surfaces which are also coplanar withand constitute an extension of the upper faces of the plywood facings ofthe panels so that all of the panels and stringers present at the top ofthe system a continuous uninterrupted planar surface on which the wetconcrete is poured for slab-forming purposes. The ends of the Steel-Plypanels, instead of being supported on the upper portions of thestringers as is conventional, are supported upon horizontal angle barswhich are movably carried on the sides of the stringers, such stringersbeing ordinarily in the form of steel I- beams. The ends of theSteel-Ply panels rest upon the upper edges or flanges of these bars andthe bars are movable between an elevated position where they maintainthe panels in exact horizontal register with the top surfaces of thestringers and a lowered position wherein the ends of the panels aredropped below the level of the upper faces of the stringers. Thus, inthe lowered position of the angle bars of the stringer assemblies, theends of the panels are free and, by proper manipulation, the panels maybe removed from beneath the partially hardened concrete slab while, atthe same time, the position of the stringers in supporting relationshipwith respect to the slab is not disturbed. The slab thus remainssupported during panel-removing operations. By such an arrangement, atno time is there relieved the upward supporting pressure that is exertedby the shores and stringer assemblies of the building erecting systemagainst the underneath face of the concrete slab. The presentpanel-supporting bracket, when operatively associated with a plain sheetor panel of plywood, produces, in elfect, a composite panel structurewhich may be physically and functionally substituted for a Steel-Plypane, of equivalent longitudinal and transverse dimensions. Thisstructure not only affords a plywood facing which lies in the same planeas the flat upper edges of the stringers upon which the structure issupported, but also is capable of manipulation in the manner of aconventional Steel-Ply panel, both in its application to the adjustablestringer assemblies and in its removal therefrom after the pouredconcrete has become hardened to such an extent that it isself-supporting.

The provision of such a panel-supporting bracket constitutes theprincipal object of the invention and, in carrying out this object, theinvention contemplates the provision of a novel end support or bracketfor one end of a plain rectangular sheet or panel of plywood which is toprovide a necessary panel facing. This end support or bracket, when usedin combination with an identical end support or bracket at the other endof the sheet or panel of plywood, establishes a substitute panelstructure for a Steel-Ply panel. Each end support or bracket possessesall the physical attributes which are provided at each end of aSteel-Ply panel in that it interlocks with the associated adjustablestringer assembly in the same manner as the Steel-Ply panel so that itmay be applied to and removed from the associated stringer assembly bythe same operations that are performed when an end of a Steel-Ply panelis applied to and removed from its associated stringer assembly.Additionally, the two end supports or brackets at the ends of the plainplywood sheet or panel afford a pair of cradles for receiving thereinthe ends of two rectangular Wooden beams which may be of the 4" x 4"variety. These beams span the distance between adjacent but spaced apartadjustable stringer assemblies and constitute base supports for theplywood sheet or panel which may be suitably tacked thereto near thecorners of the plywood sheet and removed therefrom when the thusconstructed substitute panel structure has served its purpose.

It is a further object of the present invention to provide apanel-supporting bracket of the character briefly outlined above whichmay be constructed in its entirety of conventional steel stock materialssuch as flat strip stock, angle stock and rod stock, out to length, bentto shape and all welded together to form the composite unitary rigidbracket of the present invention.

Numerous other objects and advantages of the invention, not at this timeenumerated, will readily suggest themselves as the nature of theinvention is better understood.

In the accompanying two sheets of drawings forming a part of thisspecification, one illustrative embodiment of the invention is shown.

In these drawings:

FIG. 1 is a fragmentary perspective view of a typical concrete buildingerecting system involving the formation of a horizontally disposedconcrete slab, and showing a number of Steel-Ply panels and a pair ofsubstitute panels employing the panel-supporting brackets of the presentinvention operatively applied thereto, the different panels beingillustrated for purposes of comparison;

FIG. 2 is a fragmentary top perspective view of a portion of suchsystem, the view being taken in the vicinity of one of thepanel-supporting brackets of the present invention;

FIG. 3 is a sectional view taken along the vertical plane indicated bythe line 33 of FIG. 2 and in the direction of the arrows;

FIG. 4 is a top plan view of the structure shown in FIG. 3;

FIG. 5 is a vertical sectional view taken on the line 55 of FIG. 3; and

FIG. 6 is an enlarged sectional view taken on the vertical planeindicated by the line 6-6 of FIG. 2 and in the direction of the arrows.

Referring now to the drawings in detail, and in particular to FIG. 1,there is disclosed in this view a typical concrete building erectingsystem involving a horizontal supporting surface for use in theformation of a concrete slab (not shown) resulting from the pouring ofconcrete on such surface. The entire system is designated in itsentirety by the reference numeral 10 and involves a plurality ofvertically disposed shores 12 the upper ends of which serve to supportin opposed but spaced apart relation a plurality of horizontallyextending adjustable stringer assemblies 14. Such adjustable stringerassemblies, in turn, serve to support the end regions of a horizontalseries of transversely disposed panels 16, these panels being in theform of conventional Steel-Ply panels. The Steel-Ply panels 16 have beendisclosed herein solely for purposes of comparison with a substitutepanel which is capable of being formed by utilizing two of the bracketsof the present invention, together with certain articles of lumber in amanner that will be set forth presently. Each substitute panel that isillustrated in the drawings hereof is designated in its entirety by thereference numeral 17. In erecting the system 10, the shores 12 are setup in the usual manner of erection on sills or bases (not shown) whichare positioned upon the ground or other foundation surface and serve toprelocate the vertically disposed shores. It is to be understood thatthe various shores 12 may be cross-braced in any suitable manner bystruts, the latter having been omitted herein since they form no part ofthe present invention.

The system 10 is merely illustrative of a typical concrete buildingerecting system in which the shores 12 are arranged in threespaced-apart, longitudinally extending rows and with the panels 16having their own longitudinal direction extending transversely of thesystem 10 between the adjacent parallel stringers 14. The panels 16 areconventional Steel-Ply panels of the type that is shown and described inaforementioned Patent No. 2,997,- 769, and they are in the form ofshallow rectangular box-like structures of tray-like design. Each panelincludes a plywood facing 18 which is bounded by marginal steel framemembers including elongated side members 20 and end members 22.Steel-Ply panels of this character are made up in standard sizes,specifically in three, four, six and eight foot lengths and in one, oneand one-half, two, four, six, eight, ten, twelve, fourteen, sixteen,eighteen, twenty and twenty-four inch widths, any combination of suchlengths and widths being available. The side members 20 and end members22 of each panel constitute a rectangular metal frame or studding forthe polywood facing 18.

The adjustable stringer assemblies 14 are of the type shown in theaforementioned Patent No. 3,052,008 and each assembly comprises astringer proper in the form of an I-beam (see FIG. 2) having upper andlower horizontal flanges and 32 and an interconnecting vertical web 34.The web 34 of each stringer is provided with a series of arcuate slots36 at spaced regions longitudinally of the I-beam. On opposite sides ofthe web of each stringer and in straddling relationship with respectthereto, are two vertically movable, horizontally positioned supportbars 38 in the form of angle pieces having horizontal flanges 40 andvertical flanges 42. The horizontal flanges 40 of the support bars ofeach adjustable stringer assembly project outwardly beyond the lateralextent of upper flange 30 of the I-bearn and a series of spaced apartrivets 44 project upwardly from the upper surface of the horizontalflanges 40 near the outer edge thereof. These rivets are provided as aprecautionary safety measure to prevent accidental dislodgment of theSteel-Ply panels 16 which have their end members 22 resting on thehorizontal flanges 40 when the panels are operatively assembled on thesupport bars 38 of the stringer assemblies.

Clamping bolt and nut assemblies 46 project through the slots 36 (seeFIG. 6) and also through holes 48 in the vertical flanges 42 of thesupport bars 38 in order that the movable support bars may be clamped ineither a raised or elevated position or a lowered position. The movablesupport bars are adapted to be clamped in their uppermost position withthe end members 22 of the Steel- Ply panels 16 supported thereon andlying behind the rivets 44. The various panels 16 when in theiroperative position bridge the distance between adjacent stringerassemblies 14 and the upper faces of the polywood facings 18 lie in thecommon plane of the upper flanges 30 of the I-bearn stringers so thatthere is provided a smooth unbroken surface on which wet concrete may bepoured for production of a floor slab. In order to remove the panels itis merely necessary to loosen the nut and bolt assembly blies 46 andlower the support bars 38, whereupon the panels 16 are released forremoval purposes. To remove any given panel it is merely necessary toraise the panel until the ends thereof clear the rivets 44 on thehorizontal flange 40 of the adjacent support bars 38, after which thepanel maybe shifted bodily endwise in one or the other direction inorder to cause one end of the panel to clear its associated support bar38. Thereafter, such end of the panel may be lowered and the entirepanel pulled out from beneath the partially hardened slab. -F or a moredetailed discussion of the manner in which the Steel-Ply panels 16 maybe operatively installed in and removed from a concrete buildingerecting system similar to the system 10, reference may be had toaforementioned Patent No. 3,130,470.

From the above description, it will be apparent that, according to thepreviously described arrangement of stringer assemblies 14 and Steel-Plypanels 16, it is possible to remove the panels 16 while allowing thestringer assemblies 14 to remain their supporting position with respectto the poured concrete slab with the latter resting upon the upperflanges 30 of the I-beams so that at no time is the supporting pressureon the slab relieved except in the limited area which were occupied bythe panels prior to removal. Because of this fact, it is possible toresort to panel-removing operations at a comparatively early date afterconcrete pouring operations have been effected since it is not necessaryto wait until the concrete has attained suflicient strength to beself-supporting between stringer assemblies which are twice or threetimes removed from one another.

It has been suggested previously in the introductory part of thisspecification, and in considerable detail, that the cost of Steel-Plypanels, whether on a rental or a purchase basis, makes it economicallyexpedient for a building contractor who has access to a source ofinexpensive lumber to fashion his own panels, utilizing plywood facingsand wooden studding. In such an instance, such a contractor heretoforehas been precluded from availing himself of the facilities for earlypanel removal which are ofiered by the adjustable stringer assemblies 14of the system 10. According to the present invention, a novel compositebracket which is designated in its entirety by the reference numeral 50has been devised and this bracket, when employed in connection withanother and identical bracket, together with a sheet or panel of plywoodand a pair of wooden beams of the 4 x 4" variety, enables a contractorto fashion in the field a substitute panel such as the panel 17 which,although sacrificing some of the advantages of a regular Steel-Plypanel, nevertheless may be functionally and physically substituted forone of the panels 16 in a concrete building erecting system such as thesystem 10 and which, when so substituted, is capable of removal in themanner previously described from beneath the poured and partiallyhardened concrete slab while allowing the stringer-type support for theslab to remain intact. Two such substitute panels have been illustratedin FIG. 1 for exemplary purposes, the remaining illustrated panels inthe system 10 being of the Steel-Ply type. It will be understood, ofcourse, that the disclosure is only for purposes of comparison and in anactual installation all of the various Steel-Ply panels 16 will bereplaced by corresponding substitute panels 17.

The details of the present panel-supporting brackets 50 are disclosed inFIGS. 2 to 6, inclusive, only one such bracket 50 being illustrated inFIG. 2 at one end of the substitute panel 17. It will be understood, ofcourse, that the other end of the panel has associated therewith anidentical panel-supporting bracket 50.

The panel-supporting bracket 50 of FIGS. 2 to 6, inclusive, is ofunitary welded four-piece construction and it involves in its generalorganization a horizontally extending angle bar 52 having a horizontalflange 54 and a vertical flange 56. The end portions of the angle bar 52have welded thereto similar U-shaped cradle structures 62. These cradlestructures have outer sides 64, inner sides 66 and bottoms or bases 68.The cradle bases 68 are provided with nail-receiving holes 70 therein,the purpose of which will be made clear presently. Said cradle bases 68are spaced forwardly from the vertical flange 56 of the angle bar 52 anappreciable distance so that portions of the cradle sides 64 and 66overhang these bases in an inward direction, i.e., in a direction towardthe angle bar 52. These overhanging portions are cut away to provideupper notches 58 (see FIG. 6) which present downwardly facing horizontalsupporting shoulders 59' and vertical shoulders 61, and lower notches 60presenting downwardly facing shoulders 63 and a vertical shoulder 65. AU- shaped handle 72 has its end regions welded to the underneath side ofthe horizontal flange 54 of the angle bar 52 and projects downwardly andinwardly therefrom at an angle of approximately 45, the handle beingsubstantially centrally located on the angle bar 52.

To construct one of the substitute panels 17, two pieces of lumber inthe form of 4" x 4 lumber stock are cut to provide a pair of beams 74.The opposite ends of these beams are caused to be seated withincorresponding cradles 62 of a pair of opposed brackets 50, andthereafter dual-headed nails 76 are driven upwardly into the end regionsof the beams through the small holes in the bases 68 of the cradles 62in order fixedly to secure the ends of the beams in the cradles. The twobrackets 50 and the two beams 74, when assembled in the manner justdescribed, constitute a skeleton structure for one of the substitutepanels 17. This skeleton structure may be operatively installed in thebuilding erecting system 10 in the same manner as the installation of aSteel-Ply panel 16, the installation being eflected by causing one ofthe brackets 56 to be supported on the horizontal flange 40 of one ofthe movable support bars 38 with the various downwardly facing shoulders59 resting on the horizontal flange 40 of the support bar, and with theouter edge of the support bar 38 bearing against the vertical shoulder61. Thereafter, the skeleton structure may be raised to a substantiallyhorizontal position until the level of the shoulders 59 at the other endof the skeleton structure is at least as high as the adjacent movablesupport bar 38,

after which the entire assembly may be slid to a position wherein thelower edges of the vertical flanges 56 of the angle bars 52 and thevarious shoulders 59 come to rest upon the two opposed angle bars 38 asshown in FIGS. and 6. In this position of the skeleton structure, thevarious shoulders 61 engage the outer edges of the angle bars 38 andstabilize the stringer assemblies 14 by preventing them from tiltinginwardly toward each other. The lower edges of the vertical flanges 56lie behind the rivets 44, thus insuring against possible slipping of thebrackets 50 from the supporting ledges that are offered by the anglebars 38, and also preventing spreading of the stringers laterally awayfrom each other. Such application of the skeleton structure may be madeby a workman from beneath the level of the stringers.

The lumber stock of which the beams 74 are formed is cut to apredetermined length so that the beams afford the necessary clearance attheir ends for such endwise shifting of the skeleton structure in eitherdirection. After the skeleton structure, including the two brackets 50and the two beams 74, has thus become supported upon the two verticallymovable or adjustable support bars 38, such bars are shifted to theirraised positions and clamped in such positions by the nut and boltassemblies 46. With the skeleton structure thus supported upon theelevated support bars 38, a rectangular sheet or panel of plywood 78,the longitudinal and transverse dimensions of which correspond to thedimensions of the plywood facing of a conventional Steel-Ply, is thencentered upon the skeleton structure so that it rests upon the upperfaces of the two beams 74 and is caused to fit snugly between theopposed inner longitudinal edges of the two upper flanges 30 of theparallel I-beam type stringers between which the installation is made.The plywood sheet or panel 78 will overhang the out-er edges of theparallel beams 74 a slight distance as shown in FIG. 2 and thetransverse end edges of the panel 78 will overlie and conceal thehorizontal flanges 54 of the angle bars 52. A few small nails 80 may bedriven through the panel 78 at appropriate widely spaced regions, thussecuring the panel to the beams to the end that it is held againstlateral shifting with respect thereto. In the final operation oferecting the system 10, the various substitute panels 17 may be slidsidewise longitudinally on the supporting flanges 40 until the variousopposed edges of the plywood panels 78 meet each other and form a smoothcontinuous unbroken planar slab-supporting surface on which wet concreteis adapted to be poured.

After a given building erecting system employing the substitute panels17 has served its purpose and the concrete of the poured slab has becomepartially hard but self-supporting, the substitute panels 17, includingthe brackets 50 and the beams 74 may be individually removed in themanner previously set forth in connection with the removal of standardSteel-Ply panels 16. After the support bars 38 have been lowered so asto drop the series of substitute panels 17 a slight distance, anindividual panel may be removed by raising one end thereof and slidingsuch end thereof endwise on the shoulders 63 'and away from the rivets44 on the associated flange 40, raising the other end of the substitutepanel above the level of the rivets at that end of the panel, shiftingthe panel endwise so that the raised end thereof clears the adjacentflange 40, lowering such end and, finally, lifting the other end of thesubstitute panel from the associated flange 40, thus freeing the panelfor removal from the system. During these operations the two handles 72facilitate handling of the substitute panels.

The substitute panels 17 which utilize the brackets 50 of the presentinvention as a basis for their assembly are capable or reuse in asucceeding building erecting sys tem or at a different location in thesame system. They are also capable of ease of dismantlement since only avery few nails 80 are employed to secure the plywood panels 78 on thebeams 74. Similarly, the use of dual-headed nails such as the nails 76facilitate removal of the ends of the beams 74 from the cradles 62. Thelumber stock that is used in the assembly of the substitute panels 17may thus be salvaged for use in the assembly of other substituted panelseither of the same size or of a smaller size.

The invention is not to be limited to the exact arrangement of partsshown in the accompanying drawings or described in this specification asvarious changes in the details of construction may be resorted towithout departing from the spirit or scope of the invention. Therefore,only insofar as the invention has particularly been pointed out in theaccompanying claims is the same to be limited.

Having thus described the invention what I claim as new and desire tosecure by Letters Patent is:

1. In a concrete slab form system, the combination with a pair ofhorizontally extending, elongated panelsupporting stringers disposed inspaced apart parallel relationship, each stringer including a verticallyshiftable horizontally disposed support bar movable between an elevatedand a lowered position and presenting an upwardly facingpanel-supporting led-ge thereon, and means for releasably securing saidbar in its raised position, of a panel-supporting frame structurebridging the distance between adjacent stringers and having its oppositeends resting upon the ledges of the two stringers, said frame structurecomprising a pair of elongated beam-supporting brackets, one for eachstringer, removably supported on said ledges respectively andcoextensive with a limited portion thereof, portions of said brackets ateach end thereof overhanging said ledges, cradle structures supportedfrom said overhanging portions and projecting below the level of saidledges, a pair of beams extending between the corresponding cradles ofthe two support bars and having their opposite ends seated in thecradles, and a horizontal rectangular panel supported upon said beamsand bridging the distance between said stringers.

2. In 'a concrete slab form system, the combination set forth in claim 1and wherein each beam-supporting bracket includes an angle bar providinga vertical flange and a horizontal flange, the overhanging portions ofthe bracket are in the form of outer side flanges at the ends of theangle bar, the inner side flanges spaced inwardly from the ends of thebar, and said cradle structures comprise upright U-shaped members formedfrom flat sheet metal stock having vertical outer sides secured to andsupported from said outer side flanges, inner vertical sides secured toand supported from said inner side flanges, and flat horizontalconnecting base portions, there being nail holes in said base portions,and nails projecting through said holes and into the end regions of thebeams for securing said end regions within the cradles.

3. In a concrete slab form system, the combination set forth in claim 1and wherein each beam-supporting bracket includes an angle bar providinga vertical flange and a horizontal flange, said vertical flange restingupon an adjacent ledge, and a plurality of upstanding protuberancesformed on each ledge behind which said vertical flange normally rests onthe adjacent ledge.

4. In a concrete slab form system, the combination set forth in claim 1and including, additionally, U-shaped handles formed of rod stock,having their ends secured to said beam-supporting brackets medially oftheir ends, and depending below the level of the associated ledges.

'5. In a concrete slab form system, the combination set forth in claim 1and wherein each beam-supporting bracket includes an angle bar providinga vertical flange and a horizontal flange, and wherein the overhangingportions of each bracket are in the form of outer side flanges at theends of the angle bar, and inner side flanges spaced inwardly from theends of the bar, said cradle structures comprising upright U-shapedmembers formed from flat sheet metal stock having vertical outer sidessecured to and supported from said inner side flanges, inner verticalsides secured to and supported from said inner flanges, and flathorizontal connecting base portions having holes 9 10 therein, nailsprojecting through said holes and into the bar centrally thereof anddepending below the level of end portions of the beams for securing thelatter within the associated ledge upon which the angle bar rests. thecradles, said vertical flanges of the angle =bars resting upon adjacentledges whereby the brackets and beams References Cited supported therebyare movable bodily with the support 5 UN TED STATES PATENTS bars.1,942,093 1/1934 Goldsmith et 'al. 249-210 X 6. In a concrete slab formsystem, the combination 3,130,470 4/1964 w en et a1. 24919 set forth inclaim 5 and including, additionally, a handle formed of rod stock, bentto U-shaped form and having SPENCER OVERHOLSER Primary Examiner 10 itsends secured to the horizontal flange of each angle JONES, AssistantExaminer-

